About two years ago, I was at a conference and one of the presenters brought up her idea that a significant cause of nearsightedness is the fact that so many of us spend most of the time indoors staring at computer screens, or in confined enough urban spaces that we don't keep our eyes practiced at looking far into the distance. Turns out, she wasn't too far off, though getting out in the open more is less about using our eyes for watching the distance and more about getting some sunlight. New research shows that if we want to prevent nearsightedness, we need to get outside into the sun. CNN conducted an interview with Kathryn Rose, a leading international researcher of visual disorders at the University of Sydney's Faculty of Health Sciences, and the person behind a new study showing that while doing close-up activities like reading for too long may cause myopia (though no studies have confirmed this relationship among kids and their beloved video games and the like), the real issue is how much sunlight we're getting.

When CNN asks if there is a connection between outdoor activities and a decrease in myopia among children, Rose response that yes indeed, studies have proven there is a correlation. Rose states:

Our hypothesis that the mechanism of the effect of light was mediated by retinal dopamine, a known inhibitor of eye growth whose release is stimulated by light, has also been supported by animal experiments. All of these studies confirm a consistent link between the time spent outdoors and the prevention of myopia, possibly crucially mediated by the at least ten-fold increase in light levels between indoor lighting and being outside. So yes, it is highly likely that there is a direct connection between time spent outside and preventing myopia.

In other words, getting a few hours of real sunlight can help stave off myopia in kids -- and that means there's a whole new reason for recess and outdoor activities like gardening or field trips into parks and nature reserves to be a most important part of the education program. But it doesn't stop there.

The study found that children need 10-14 hours outside per week in addition to what time they spend outside during school. And that means parents still have a good reason to get kids out of the house and away from television sets and video games.

When asked whether or not location matters, such as living in a country that gets less sunlight during winter, Rose states that it doesn't seem to matter, in part because people with limited sunlight during winter seem to spend more time outside during summer and that could balance out the lack of light in winter.

While there is more work to be done to find out more about how and why sunlight could affect nearsightedness, one thing is for sure -- you have a brand new excuse to get outside and enjoy the day. Your eyes depend on it!